Check for python interpreter at configure time and document the requirement.
[pspp] / tests / math /
drwxr-xr-x   ..
-rw-r--r-- 3978 chart-geometry.at
-rw-r--r-- 2395 chart-get-scale-test.c
-rw-r--r-- 2821 chart-get-ticks-format-test.c
-rw-r--r-- 1924 moments.at
-rw-r--r-- 169884 randist.at